package com.entity.weixin;

import java.security.MessageDigest;

public class MD5Util {

    private static String byteArrayToHexString(byte b[]) {
	StringBuffer resultSb = new StringBuffer();
	for (int i = 0; i < b.length; i++)
	    resultSb.append(byteToHexString(b[i]));

	return resultSb.toString();
    }

    private static String byteToHexString(byte b) {
	int n = b;
	if (n < 0)
	    n += 256;
	int d1 = n / 16;
	int d2 = n % 16;
	return hexDigits[d1] + hexDigits[d2];
    }

    public static String MD5Encode(String origin, String charsetname) {
	String resultString = null;
	try {
	    resultString = new String(origin);
	    MessageDigest md = MessageDigest.getInstance("MD5");
	    if (charsetname == null || "".equals(charsetname))
		resultString = byteArrayToHexString(md.digest(resultString.getBytes()));
	    else
		resultString = byteArrayToHexString(md.digest(resultString.getBytes(charsetname)));
	} catch (Exception exception) {
	}
	return resultString;
    }

    private static final String hexDigits[] = { "0", "1", "2", "3", "4", "5", "6", "7", "8", "9", "a", "b", "c", "d",
	    "e", "f" };

}
